We had a double sunset last night. There was a brilliant sunset in the west but also another, not as large or dramatic but still very pretty in the east. The technical name for this is back-scattering.
Some smart people at Quora tell us:
The pinkish band is known as the Belt of Venus and is visible from shortly before to about 15 minutes after sunset. It is also visible in the west at sunrise. It will become darker and more purple as twilight deepens. After about 15 minutes, it will not be visible anymore and the whole sky will appear dark blue.
It is caused by the reddened sunlight being back-scattered by particles in the atmosphere. What you are seeing is basically the light from the setting/rising sun being projected into the sky opposite the sun’s direction and the particles in the atmosphere scatter the light back. Almost always (none when the sun is still visible) there is a darker segment that is visible below the pink band. This is the earth’s shadow and it will rise higher and “invade the sky” as twilight progresses.
I've searched for images of this but to no avail. If I'd realised that it was a very rare happening I'd have got my camera out. The above photograph is one that The Old Girl took from McLeod Bay many years ago and is looking west in the evening. The kayaker is a friend of ours, Alan. If I'd spotted the twin sunsets earlier I'd have got my digital camera out and found a spot where I could get a view of both 'sunsets' in the same frame. Maybe it will happen again tonight.
It's 'stinking' hot today - blue sky, no wind and blazing sunshine. I played tennis this morning but we called it quits before eleven. I came home and went for a swim, staying in the water much longer than usual.
3 comments:
You're becoming a bit of a sunset bore.
Thanks mum for the great retorts.
No, it was silent.
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